Description

When adding Notes to blocks inside a post or page, the Notes appear correctly aligned with their corresponding blocks in the floating sidebar.
However, if you switch to the Code Editor and then exit back to the Visual Editor, all previously added Notes incorrectly shift to the top of the floating comments sidebar, losing their original positions.

This makes the Notes appear detached from their associated blocks and impacts usability when reviewing or navigating Notes.

Step-by-step reproduction instructions

1. Open any post or page in the block editor.
2. Add Notes to a few different blocks.
3. Ensure the Notes appear correctly aligned in the floating sidebar.
4. Switch to Code Editor.
5. Exit the Code Editor and return to the Visual Editor.
6. Observe the floating sidebar.

Screenshots, screen recording, code snippet

Environment info

• WordPress 6.9-RC1
• Chrome Version 142.0.7444.135
• Macbook Pro
• Gutenberg Version 22.1.0-rc.1

Please confirm that you have searched existing issues in the repo.

• Yes

Please confirm that you have tested with all plugins deactivated except Gutenberg.

• Yes

Please confirm which theme type you used for testing.

• Block
• Classic
• Hybrid (e.g. classic with theme.json)
• Not sure